Racks for carrying luggage and other articles on an exterior surface of automobile vehicles and the like have become quite popular. Typically, such racks and carriers are mounted on the vehicle roof or rear trunk lid, although other surfaces are sometimes used, such as the upper surface of a cap or canopy for a pick-up truck.
There are many prior art patents on such luggage racks and article carriers. One general type rack employs raised side rails mounted substantially above the surface of the vehicle on fixed stanchions with relatively flat intermediate skid strips or load supporting slats therebetween. Bott Re. 26,538 and Re. 26,539 are examples of expired patents of this kind. Ingram U.S. Pat. No. 4,225,068; Kowalski U.S. Pat. Nos. 4,239,138 and 4,279,368 and Mareydt U.S. Pat. No. 4,616,772 are more recent examples disclosing luggage racks and carriers of this general type. Because the side rails are elevated above the roof surface, they create undesirable wind resistance and noise and because they are unsupported between the stanchions, their load carrying capacity is somewhat limited.
Another general type of rack or carrier that has met with some commercial acceptance employs relatively flat, low-profile slats along the sides on which stanchions connected to cross bars or article tie down members are mounted. Bott U.S. Pat. No. 4,516,710 and Re. 32,706 along with their issued parent patents and many of the numerous references cited therein are illustrative of this style rack. Other U.S. patents disclosing racks and carriers of this type are: Ingram U.S. Pat. Nos. 4,132,335 and 4,244,501; Kowalski et al. U.S. Pat. No. 4,372,469; Rasor et al. U.S. Pat. No. 4,406,386; Cronce U.S. Pat. No. 4,448,337; Stapleton et al. U.S. Pat. No. 4,469,261 and many of the references cited in these patents. The side slats disclosed in these patents are generally characterized as being substantially wider than they are high and have a substantially flat, horizontal upper article carrying surface.
For use with vehicles having roof surfaces with a more rounded contour, Bott U.S. Pat. Nos. 4,684,048 and 4,754,905 disclose carriers having supporting side slats with non-horizontal lower mounting surfaces and upwardly opening channels for receiving generally horizontally disposed liners with flat inwardly directed flanges for supporting articles and movable stanchions connected to cross bars.
More recently, luggage racks have been designed wherein the side rails are supported on the exterior surface of the vehicle but the rails are higher than they are wide and are provided with a decorative trim strip on the outboard side of the rail to present a streamlined aerodynamic and aesthetically pleasing appearance. Such a luggage rack is disclosed in the above-mentioned copending Mandarino et al. U.S. patent application Ser. No. 250,705 which also discloses article securing members in the form of crossbar stanchions or tie down elements that are longitudinally movable along the side rails and selectively locked in place at predetermined intermittent locations by a pushbutton lock pin mechanism that engages spaced apart apertures formed along the length of the rails. As disclosed in that application, the push button is formed with a sloping cam surface that engages a complementally angled cam follower that lifts a spring biased locking pin out of engagement with one of the apertures in the side rail. While this arrangement is generally satisfactory, the friction caused by the angled cam faces as well as foreign material such as dirt, ice and water on the cam surfaces sometimes causes the button to bind making it difficult to depress in order to lift the lock pin or to properly release the button under the bias of the spring to reinsert the lock pin in another aperture in the side rail.